BAN #235: Rotten to The Core

13 July 2020   Issue #235

[Spiral Galaxy M81 image credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona]

Subscribers are layered and magnetic and hot and worldly.


I love scifi. Sometimes it doesn’t love me back.

I have tried, in my life lately, to be less of a dick. In some ways it’s easy, because I used to be something of a monumental jerk in some circumstances. For example, I don’t review movies any more, because it’s too easy to become a smug, superior, self-serving… well, dick.

As a not terribly random example, here’s my review of the movie “The Core”, which I put up on my old Bad Astronomy site when the movie came out in 2003. You can probably smell the smugness right through that link.

Why this example? Because I recently wrote a blog post about a pair of gigantic blobs of material in Earth’s mantle that affect our geomagnetic field, including rapidly changing the location of the Earth’s magnetic north pole. In it, I make a little reference to “The Core” near the end (“Short of getting Aaron Eckhart and Stanley Tucci to detonate nukes down there, there's not much we can do anyway”) just for fun.

[Credit: Paramount Pictures]

That made me think about the movie, and because I had a little downtime recently I decided to watch it again — it’s on Amazon Prime for now, if you care. And yeah, the science of it is hit or miss, with some really good stuff (like describing the internal layers of the Earth) with some that’s not so good (microwaves aren’t affected by magnetic fields, and can’t cook the Earth). Overall it’s a fun movie, with a lot of silliness mixed in with some great performances (I mean, c’mon, Stanley Tucci).

But then, in my rewatch, I got to one point in the movie and was shocked. As the heroes of the movie are about to fix everything (by detonating nukes outside Earth’s inner solid iron core to get it rotating again, which comes in under the not-so-good science) they discover the liquid iron outer core is less dense than predicted, throwing off their calculations. I won’t spoil what happens, but as I watched this something about this rang a bell…

[The layers of the Earth. Credit: 2020 Kelvinsong - CC BY-SA 3.0]

… and then I suddenly remembered I had written about exactly this in this very newsletter! In BAN Issue 212 I have an article about scientists investigating the properties of Earth’s outer core (issue is for paid subscribers; here’s the news article itself), where they found it’s 8% less dense than expected if it were composed entirely of liquid iron.

Huh. The movie was, um, right. I mean, it’s coincidence, but still.

Here’s the thing: I try not to be a dick anymore, and sometimes that means making amends. And that brings me to a slight tangent. Bear with me.

Some years ago I was at San Diego Comic Con, at a party. My friend Amy Berg saw me, and a look of evil mischievous delight spread across her face (she’s good at this, being evil and mischievous and utterly delightful; and if her name is familiar it’s because she worked on that show you like). She says she has a friend I have to meet, and drags me over to him.

I knew something was up, but didn’t know what to expect. She squares me up in front of a man and says to him, “John, this is Phil Plait. Phil is an astronomer who wrote the Bad Astronomy review of ‘The Core’.” Without pause she then turns to me and says, “Phil, this is John Rogers. He wrote ‘The Core’.”

The look of mischief in her smile turned to one of anticipatory glee as she expected us to be at the other’s throat.

[My favorite picture of Amy Berg and me. Credit: Phil Plait]

Sadly for her, we disappointed her. I said something to the effect of, “Oh wow, cool! It’s great to meet you!” and he responded with the equivalent of “Oh, nice, I like your stuff!” and then we proceeded to bond and laugh and gush and generally have a great time.

I love Amy dearly with all my heart, but I also know I will eternally delight in never letting her live this down.

So. Returning from that tangent. When I realized that the movie had in fact predicted the lower density of Earth’s outer core, I knew what I had to do. I looked up John’s address and sent him an email with the subject line “Rotten to ‘The Core’”, where I gave him a link to the science article and added, “OH MY GOD. I owe you and the movie an apology. You were absolutely right.”

He sent me a lovely note in return, and all is good in the world, if one layer of that world has slightly less density than previously thought.

Another tangent: I was pleasantly surprised while watching the opening science of “The Core” to see that my pal Rekha Sharma was in it! I’ve run into her a few times at cons and such; she’s an actor you may know from playing the headstrong and impulsive Commander Ellen Landry in Star Trek: Discovery, or possibly as playing Tory Foster in a small local production called Battlestar Galactica. She too is delightful and funny and taught me how to use Instagram better. It’s fun to rewatch some older show or movie and see someone who wasn’t well known at the time, but has risen to a level of fame since.

[Rekha Sharma and me after the Star Trek Cruise in 2019. Credit: Phil Plait]

So there you go. I regret a lot of attitudes and behaviors I had in the past, and I’m very glad I’ve had the opportunity to learn from them and grow, as much as some of them still make me wince with shame when the memory of them suddenly infiltrates my brain late at night.

But this is one that led to a pretty cool outcome. It’s nice, even on such a small scale as this, to see the arc of my personal timeline bending toward joy.

Blog Jam

What I’ve recently written on the blog, ICYMI

[An amazing mosaic of the Moon processed in a special way to highlight topography. From Tuesday’s article. Credit: Andrew McCarthy]

Monday 6 July, 2020: A record-breaking quasar poses a supermassive problem

Tuesday 7 July, 2020: Terminator: Moon

Wednesday 8 July, 2020: The fastest spinning star in the galaxy

Thursday 9 July, 2020: More black hole weirdness: They bend light so much they self-illuminate

Friday 10 July, 2020: Pluto’s far side: Exploring the backside of a tiny iceworld

Et alia

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